Printing machine



April 27 1926.

A B EVANS PRINTING MAciINE Filed Jan 18, 1923 2 Sheets-Sheet 2 Fig.4.

Inventor w .i, Lo 7 Attorney.

Fig. 5.

Patented: Apr. 27,1926, 7

I ARTHUR BURROUGHES EVANS, F LEEDS, ENGLAND.

PRINTING MACHINE.

Application filed January 18,1923. Serial No. 613,409.

To all /10 172 2'2? may concern.

Be t known that I, ARTHUR BURROUGHES EVANS, a sub ect of the King of Great Britain and Ireland, residing at 7 Wood land Grove, Leeds, England, have invented certain new and useful Improvements 111 Printing Machines, of which-the following is a specification.

In printing machines in which it is neces 10 sary to fasten plates, blankets, or the like with plane surfaces, around the periphery of a cylinder, there is, in the case of a small gap in the cylinder, difficulty in drawing the plate or the'like taut upon the periphery of the cylinder, and in register with its requiredposition. in the machine.

According to the invention means are provided for mounting a flexible peripheral element such as aplate, blanket or the like.

upon a cylinder having a longitudinal gap,

the said means comprising in combination fittings such as studs or bars attached to the inwardly diverted ends of the flexible peripheral element, which are inserted within the said gap, the said fittings protruding at or near the ends of the said flexible peripheral element in oppositely disposed poSi tions within the gap, and tensioning means for the said flexible peripheral element disposed between the said respective fittings and adjustable in a plane passing through the axis of the cylinder, said tensioning 'means being adapted toen-gage the said fittings by contact without positive connection and to disengage'on movement of the said tensioning means.

inafter described.

The invention comprises the features here- The invention is illustrated by way of ex ample in. the accompanying drawings in wluch- V p v Flgure 1 1s a sectional end elevation of a cylinder at the part at which the gap is provided and showing means for carrying out the invention.

bar shown inFi'gure 1. I

Figure 3 1s a plan corresponding to F g Figure 2-is a detailed elevation of the ure 2 but shewing two bars instead of one,

for engaging the respective ends of the plate or blanket.

Figure 4 is an elevation of a sectional form of the bar.

ure 4.

' h are in register with thestuds or bolt heads Figure 5 is a plan corresponding to Fig Figure 6 is a sectional elevation similar to Figure lbut showing a constructional modification. p v I Figure 7 is a detail plan corresponding to Figure 6, and V c Figure 8 is aplan alternativeto that illustrated in Figure 7. c I

In the drawings a shows in section a part of .a cylinder at the position at which the longitudinal gap is formed. Z are plates or Lablanket-s used for printing, '0 are screws used for tensioning the plates or. blankets in the manner hereinafter described and are disposed in a plane passing through the axis of the cylinder. Holes are drilled or punched in the plates or blankets Z) to a standard gauge and through these holes is inserted as illustrated on the left hand I side of Figure 1 a stud or bolt (Z fastened by a nut e. As thehead of the stud or bolt 7 (Z is tapered it engages with a corresponding and substantially semi-circular and under-cut recess hill the bar 9 in the manner I of ahookl,

According to a modification illustrated the plate or blanket b to a longitudinal stiffening piece f which reinforces theplate or blanket near its edge. o

The barg in the manner hereinbefore described is provided withrecesses h at each side and is supportedupon the cylinder bythe screws 0 within the gap.

It will be understood that the recesses cl. Upon'the lower ends'of each of the screws 0, and'between the lower face of the bar 9 and the cylinder, a spiral spring 7; is mounted by which the bars 9 are thus supported upon the screwa when not engaged withthe studs or bolts d.

It will be understood that the loose edges of the plate or blanket e are inserted in the gap of the cylinder in such manner that the W) heads of the studs or boltsul engage with the recesses 7b and the bar 9 is thereupon I caused to tighten the plate/or blanket b by theadjustment of the screws 0.

' In Figure 3 is indicated a method of us W71 ing two bars, one engaging the front edge and one the rear edge of the plate or blanket b.

As illustrated in Figure 3 the respective bars are formed alternately with bosses on the respective sides for the reception of the tensioning screws which are arranged in alignment, the bosses in one bar being ac commodated in'recesses in the other, so-that thus the bars may be disposed in close relation. By such means a very narrow gap may be provided in a cylinder with satisfactory means for independently tightening the plate or blanket at its respective ends.

In Figures 6 and 7 a stiffening piece 7' is attached to the plate or blanket 1) near its edge by being riveted through the standard holes in the plate or blanket 7; on the face opposite to that aecording' to the modification at the right hand side of Figure 1. I

In such case the ends of the stiffening pieces f are registered to theholes in the alate or blanket b and slide between the end walls in the gap of the cylinder at.

In the modification illustrated in Figures 6 and 7 instead of providing a bar, a contact block Z is provided which can be rotated upon the screw 0. Its lower part is formed with a cam surface which engages with the top face of the stiffening piece or bar j. By such means the rotation of the contact block Z through 90 quickly effects the ten sioning of the plate or blanket Z). The contact block Z at its upper part may be provided with a boss of a square shape convenient for engagement by means of a spanner or othertool.

It will thus be understood that theoperation involved in the use 01 the constructional modification illustrated in Figures 6 and 7 is similar to that involved inthe constructional modification illustrated in Figure 1.

Figure 8 at m illustrates a modification in form of the contact block Z which is provided with cam'surfaces at opposite positions so that thus by rotation in one direction the stiii'ening pieces or bars f at the respective sides of the gap" are simultaneously acted upon for applying tension on the.

plate or blanket Z).

It'will be understood that in each of the constructions described, the register of the design on the plate or blanket Z) to the cylinder and the machine in which this cylinder is placed is obtain-ed by means of the holes in the plates or blankets Z).

I claim:

1. In printing machines, means for mounting a flexible peripheral member such as a plate, upon a cylinder having a longitudinal gap, comprising in combination, elements within the said gap, carried at the respective inwardly diverted ends of the said tie ible peripheral member, the said elements protruding respectively from the ends of the said flexible peripheral member at the inner face and in oppositely disposed positions within the said gap, and tensioning means for the said flexible peripheral mem- -;ber disposed between the said respective elements, and adjustable in a plane passing approximately through the axis of the cylinder, said tensioning means comprising studs carried upon the cylinder within the said gap in a radial position and an engaging membcr mounted upon the said studs, the said engaging member and the same elements being adapted to engage by contact only at a position above the said elements, without positive connection and being adapted also to disengage on the outward movement of the said engaging member. substantially" as described.

2. In printing machines, means for mounting a flexible peripheralmember, such as a plate, upon a cylinderhaving a longitudinal gap, comprising in combination, a series of separate elements positioned upon the respective inwardly diverted ends of the flexible peripheral member within the said gap, the said elements being inserted within holes i to "med-in the inwardly diverted ends aforesaid, the said elements protruding respectively from the ends of the said flexible peripheral member in oppositely disposed positions within the said gap, and tensioning means for the said flexible peripheral member disposed between the said respective elements and adjustable in a plane passing approximately through the axis of the cylinder, said tensioning means engaging the said elements by contact without positive connection and disengaging on the movement of the said tensioning means, substantially as described.

3. In printing machines, moans "for mount ing afiexible peripheral member, such as a oppositely disposed positions within the said gap, tensioning members for the said tier;-

ible peripheral member disposed the justing screws carrying the said tensioning members and springs supporting the said 'tensioning members substantially as described. L j

ARTHUR BURRUUGHES EVANS.

, between the said respective elements, and adjustable in a plane passing approximately through axis of the cylinder, radially disposed adplate, upon a cylinder having a longitudinal 

